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Friction 2024年第8期12卷 1707-1715,F0004页

作者： Yushan CHEN liang JIANG Linmao qian Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu 610031China

Accurately measuring the coefficient of friction(COF)is the fundamental prerequisite of superlubricity *** study aimed to reduce the COF measurement resolutionΔμof atomic force microscopy(AFM).Based on the theoretical model,a distinctive strategy was adopted to reduceΔμby optimizing the cantilever’s cross-section of the AFM probe,inspired by civil engineering.Δμcan be reduced by decreasing the width of the horizontal side wR and the wall thickness t and increasing the width of the vertical side ***,the I-shape demonstrates the highest reduction inΔμ,followed by the *** the processability,the AFM probe with the U-shaped cross-sectional cantilever was investigated further,and the dimensions are 35μm wR,3.5μm wH,0.5μm t,50μm l(cantilever length),and 23μm htip(tip height).The finite element analysis results confirm its *** being fabricated and calibrated,the AFM probe achieves the minimalΔμof 1.9×10^(–6)under the maximum normal force so ***,the friction detection capability of the fabricated AFM probe improves by 78 times compared to the commercial tipless-force modulation mode(TL-FM)AFM probe with the conventional solid rectangular cross-sectional *** study provides a powerful tool for measuring 10^(–6)COF.

关键词： atomic force microscopy superlubricity coefficient of friction probe cantilever

AFM probe for measuring~10^(−5)ultra-low friction coefficient:design and application

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Friction 2024年第1期12卷 64-73页

作者： Yushan CHEN liang JIANG Linmao qian Tribology Research Institute State Key Laboratory of Traction PowerSouthwest Jiaotong UniversityChengdu 610031China

Superlubricity provides a novel approach to addressing friction and wear issues in mechanical ***,little is known regarding improving the atomic force microscope(AFM)friction coefficient measurement ***,this study established the theoretical formula for the AFM friction coefficient measurement and deduced the measurement ***,the formula was applied to the AFM probe with a rectangular cross-section *** measurement resolution is associated with the dimensional properties of the AFM probe,the mechanical properties of the cantilever material,the properties of the position-sensitive detector(PSD),and probably the anti-vibration performance of the *** is feasible to make the cantilever as short as possible and the tip as high as possible to improve the measurement *** AFM probe for measuring an ultra-low friction coefficient was designed and *** cantilever’s length,width,and thickness are 50,35,and 0.6μm,*** tip height is 23μ*** measurement resolution can reach 7.1×10^(−6) under the maximum normal ***,the AFM probe was applied to measure the superlubricity between graphene *** friction coefficient is 0.00139 under 853.08 *** work provides a promising method for measuring a~10^(−5) friction coefficient of superlubricity.

关键词： atomic force microscope(AFM) superlubricity friction coefficientμ probe

Study on the influence of food emulsion components on its lubrication characteristics and smooth perception

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Friction 2024年第11期12卷 2491-2504页

作者： Shanhua qian liang WANG Ziyan ZHENG Qichen TANG Da BIAN School of Mechanical Engineering Jiangnan UniversityWuxi 214122China Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan UniversityWuxi 214122China

Due to the increasing risk of obesity and cardiovascular diseases caused by high-fat diets,low-fat foods have become a priority demand for consumers’***,the smoothness perception and scientific assessment methods of the existing low-fat foods should be *** this study,three food emulsions were prepared,and their lubrication characteristics,sensory evaluation of smoothness,and electroencephalogram(EEG)signals were assessed to preliminarily investigate the effects of food emulsion components on their above *** results showed that fat substitute(FSU)and fat could significantly reduce coefficient of friction(CoF)of the food emulsions,with average CoF reduced by 28%and 63%compared to the original food *** addition,fat-enriched food emulsions continued to exhibit excellent lubrication characteristics after adding artificial saliva,with an average CoF reduced by 31.1%compared to that of the food emulsions without artificial *** FSU and fat improved the smoothness of food emulsions,and the lubricating properties of fat were more pronounced,with fat-enriched food emulsion which could provide a substantial improvement in smoothness compared to the fat-free food *** of subjects’EEG signals revealed that food emulsion with lower CoF and higher smoothness triggered higher P3 amplitudes and longer *** findings provide better insights into the scientific evaluation of food texture and the development of low-fat foods.

关键词： food emulsion soft friction sensory evaluation electroencephalogram(EEG)signal fat substitute

Experimental study on the effect of flexible joints of a deep-buried tunnel across an active fault under high in-situ stress conditions

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Underground Space 2024年第6期19卷 189-207页

作者： Jiawei Zhang Zhen Cui qian Sheng Wanhua Zhao liang Song State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Civil Engineering and Architecture Wuhan Polytechnic UniversityWuhan 430023China

During dislocation,a tunnel crossing the active fault will be damaged to varying degrees due to its permanent stratum *** previous studies did not consider the influence of the tunnel’s deep burial and the high in-situ stress,so the results were not entirely *** this paper,the necessity of solving the anti-dislocation problem of deep-buried tunnels is systemically *** the model test of tunnels across active faults,the differences in failures between deep-buried tunnels and shallow-buried tunnels were compared,and the dislocation test of deep-buried segmental tunnels was carried out to analyze the external stress change,lining strain,and failure mode of *** results are as follows.(1)The overall deformation of deep-buried and shallow-buried tunnels is both *** failure mode of deep-buried tunnels is primarily characterized by shear and tensile failure,resulting in significant compressive deformation and a larger damaged *** contrast,shallow-buried tunnels mainly experience shear failure,with the tunnel being sheared apart at the fault crossing,leading to more severe damage.(2)After the segmental structure design of the deep-buried tunnel,the‘‘S”deformation pattern is transformed into a‘‘ladder”pattern,and the strain of the tunnel and the peak stress of the external rock mass are reduced;therefore,damages are significantly mitigated.(3)Through the analysis of the distribution of cracks in the tunnel lining,it is found that the tunnel without a segmental structure design has suffered from penetrating failure and that cracks affect the entire *** cracks in a flexible segmental tunnel affect about 66.6%of the entire length of the tunnel,and cracks in a tunnel with a short segmental tunnel only affect about 33.3%of the entire length of the ***,a deep-buried tunnel with a short segmental tunnel can yield a better anti-dislocation effect.(4)By comparing the shallow-buried segmental tunnel in previous

关键词： Tunnel project Crossing active fault High in-situ stress Segmental structure design Flexible joint

Hyperglycemia activates FGFR1 via TLR4/c-Src pathway to induce inflammatory cardiomyopathy in diabetes

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1693-1710页

作者： Xiong Chen Jinfu qian Shiqi liang Jianchang qian Wu Luo Yujuan Shi Hong Zhu Xiang Hu Gaojun Wu Xiaokun Li Guang liang department of Endocrinology the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China Chemical Biology Research Center School of Pharmaceutical SciencesWenzhou Medical UniversityWenzhou 325035China department of Wound Repair the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China department of Cardiology the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China School of Pharmaceutical Sciences Hangzhou Medical CollegeHangzhou 311399China

Protein tyrosine kinases (RTKs) modulate a wide range of pathophysiological events in several non-malignant disorders, including diabetic complications. To find new targets driving the development of diabetic cardiomyopathy (DCM), we profiled an RTKs phosphorylation array in diabetic mouse hearts and identified increased phosphorylated fibroblast growth factor receptor 1 (p-FGFR1) levels in cardiomyocytes, indicating that FGFR1 may contribute to the pathogenesis of DCM. Using primary cardiomyocytes and H9C2 cell lines, we discovered that high-concentration glucose (HG) transactivates FGFR1 kinase domain through toll-like receptor 4 (TLR4) and c-Src, independent of FGF ligands. Knocking down the levels of either TLR4 or c-Src prevents HG-activated FGFR1 in cardiomyocytes. RNA-sequencing analysis indicates that the elevated FGFR1 activity induces pro-inflammatory responses via MAPKs–NFκB signaling pathway in HG-challenged cardiomyocytes, which further results in fibrosis and hypertrophy. We then generated cardiomyocyte-specific FGFR1 knockout mice and showed that a lack of FGFR1 in cardiomyocytes prevents diabetes-induced cardiac inflammation and preserves cardiac function in mice. Pharmacological inhibition of FGFR1 by a selective inhibitor, AZD4547, also prevents cardiac inflammation, fibrosis, and dysfunction in both type 1 and type 2 diabetic mice. These studies have identified FGFR1 as a new player in driving DCM and support further testing of FGFR1 inhibitors for possible cardioprotective benefits.

关键词： Diabetic cardiomyopathy Protein tyrosine kinases FGFR1 Cardiomyocytes Inflammatory responses Toll-like receptor4 c-Src NFkB

Evaluating the tumor stratification with a lysosomal pH sensitive-probe by fluorescence lifetime imaging

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Chinese Chemical Letters 2024年第3期35卷 262-267页

作者： Jun Yan Xing liang qian Zhang Luolin Wang Weiying Lin Guangxi Key Laboratory of Electrochemical Energy Materials Institute of Optical Materials and Chemical BiologySchool of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China

Owing to the anaerobic metabolism in the tumor,abundant acidic metabolites are produced and accumulated in the ***,the cells in different tumor layers are directly linked to the pH ***,due to the lack of robust tools,the high-efficient evaluation of the acidic micro-environment of tumor stratification faces the challenge of accurate *** designed a new pH sensitive fluorescent lifetime probe target to *** we expected,the fluorescence lifetime of PLN possesses a good linear fit to the pH value,which could detect the pH change at a single lysosome level in real time,and then evaluate the different acidity of tumor *** probe PLN is successfully used to evaluate the tumor stratification by fluorescence lifetime imaging microscopy(FLIM)for the first time,which is of great significance in the preoperative diagnosis of clinical tumor treatment or evaluation of drug delivery effect.

关键词： FLIM pH Fluorescence imaging Lysosome Tumor imaging

Two material removal modes in chemical mechanical polishing:mechanical plowing *** bonding

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Friction 2024年第5期12卷 897-905页

作者： Yuan WU liang JIANG Wenhui LI Jiaxin ZHENG Yushan CHEN Linmao qian Tribology Research Institute State Key Laboratory of Rail Transit Vehicle SystemSouthwest Jiaotong UniversityChengdu610031China

With the rapid development of semiconductors,the number of materials needed to be polished sharply *** material properties vary significantly,posing challenges to chemical mechanical polishing(CMP).Accordingly,the study aimed to classify the material removal *** on the CMP and atomic force microscopy results,the six representative metals can be preliminarily classified into two groups,presumably due to different material removal *** the tribology perspective,the first group of Cu,Co,and Ni may mainly rely on the mechanical plowing *** adding H_(2)O_(2),corrosion can be first enhanced and then suppressed,affecting the surface mechanical ***,the material removal rate(MRR)and the surface roughness increase and *** comparison,the second group of Ta,Ru,and Ti may primarily depend on the chemical bonding *** H_(2)O_(2)can promote oxidation,increasing interfacial chemical ***,the MRR increases,and the surface roughness decreases and levels *** addition,CMP can be regulated by tuning the synergistic effect of oxidation,complexation,and dissolution for mechanical plowing,while tuning the synergistic effect of oxidation and ionic strength for chemical *** findings provide mechanistic insight into the material removal mechanism in CMP.

关键词： Chemical mechanical polishing corrosion wear material removal mode mechanical plowing chemical bonding

development and Application of a Power Law Constitutive Model for Eddy Current Dampers

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2403-2419页

作者： Longteng liang Zhouquan Feng Hongyi Zhang Zhengqing Chen Changzhao qian School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen361024China Hunan Provincial Key Laboratory ofWind and Bridge Engineering Hunan UniversityChangsha410082China Fujian Provincial Key Laboratory ofWind Disaster and Engineering Xiamen University of TechnologyXiamen361024China State Key Laboratory of Bridge Engineering Safety and Resilience Hunan UniversityChangsha410082China

Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.

关键词： Eddy current damper constitutive model finite element analysis vibration control power law constitutive model

Cardioprotection of Shenfu preparata on cardiac myocytes through cytochrome P450 2J3

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Journal of Integrative Medicine 2013年第5期11卷 327-336页

作者： Yong Xiao Zeng-chun Ma Yu-guang Wang Hong-ling Tan Xiang-ling Tang qian-de liang Cheng-rong Xiao Yue Gao Beijing Institute of Radiation Medicine Academy of Military Medical Sciences School of Pharmaceutical Sciences Central South University

To evaluate whether Shenfu injection （SFI） protects against cardiac myocyte injury induced by Fupian injection （FPI） in vitro. METHODS： H9c2 cells were separately treated with FPI, Renshen injection （RSI） and SFI. Cell viability, lactate dehydrogenase （LDH） release, spontaneous beating rate of primative cardical cells, caspase-3/7 activity, cell apoptosis, and cytochrome P450 2J3 （CYP2J3） mRNA expression were analyzed. RESULTS： The viability of H9c2 cells treated with SFI （37 and 75 mg/mL） was significantly higher than that of H9c2 cells treated with FPI （25 and 50 mg/mL）（P〈0.05, P〈0.01, respectively）. LDH activity of H9c2 cells treated with SFI （75 mg/mL） was significantly decreased （P〈0.01） compared with that of H9c2 cells treated with FPI （50 mg/mL）. SFI （150 mg/mL） significantly attenuated FPI （100 mg/mL）-induced spontaneous beating rate decrease in primary myocardial cells after 4-hour treatment. Compared with FPI （12 and 25 mg/mL）, SFI （18 and 37 mg/mL） treatment could effectively reverse the change of caspase-3/7 activity （P〈0.01 and P〈0.01, respectively）. Compared with FPI （6 and 25 mg/mL）, apoptotic cells decreased significantly （P〈0.05, P〈0.01, respectively） when H9c2 cells were incubated with SFI （9 and 37 mg/mL）. The expression of CYP2J3 mRNA was down-regulated by FPI, while RSI and SFI could up-regulate the expression of CYP2J3 （P〈0.01）, which suggested the potential mechanism of protection of RSI against cardiac myocyte damage induced by FPI treatment. CONCLUSION： These observations indicate that SFI has the potential to exert cardioprotective effects against FPI toxicity. The effect was possibly correlated with the activation of CYP2J3.

关键词： Shenfu decoction cardiotonic agents cytochrome P450 2J3 plant extracts in vitro

DGS1 improves rice disease resistance by elevating pathogenassociated molecular pattern-triggered immunity

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aBIOTECH 2024年第1期5卷 46-51页

作者： Yu Wang Chuan Zheng You-liang Peng qian Chen MOA Key Lab of Pest Monitoring and Green Management and Frontiers Science Center for Molecular design Breeding China Agricultural UniversityBeijing 100193China

Rice yield and disease resistance are two crucial factors in determining the suitability of a gene for agricultural *** grain size1(DGS1),encoding an RING-type E3 ligase,has been found to have a positive effect on rice yield by regulating rice grain number and 1000-grain ***,the role of DGS1 in rice blast resistance is still *** this study,we report that DGS1 enhances disease resistance by improving PTI responses,including stronger ROS burst and MAPK activation,and also increased expression of defense-related ***,DGS1 works in conjunction with ubiquitin conjugating enzyme OsUBC45 as an E2-E3 pair to facilitate the ubiquitin-dependent degradation of OsGSK3 and OsPIP2;1,thereby influencing rice yield and immunity,***,the DGS1-OsUBC45 module has the potential in facilitating rice agricultural breeding.

关键词： Rice blast PTI ERAD E2-E3 pair Ubiquitination